Grading and drainage requirments - InspectionNews

Michael Thomas · #1 (**permalink**) 12-11-2007, 04:03 PM

We always give advice about grading away from a structure “one inch per foot for the first ten feet” or the like, but I just realized that beyond common sense I don't have a cite for the requirement. Is in the IRC, or is it some sort of standard from civil engineering, or what?

Ditto for 6' on downspout discharge from structure.

Billy Stephens · #2 (**permalink**) 12-11-2007, 04:40 PM

Michael,
I'll bite.

IRC 2003 R202 Definitions Grade Plane-------------------------Where the finished ground level slopes away from the exterior walls,----------------------------------------------.

Also: IRC 2003 R401.3 Drainage.----------------------------------The grade away from the foundation shall fall a minimum of 6 inches within the first 10 feet.

Michael Thomas · #3 (**permalink**) 12-11-2007, 06:18 PM

Thanks.

Now, about the downspouts being 6' out...

Michael Thomas · #4 (**permalink**) 12-11-2007, 06:23 PM

Also, I've got this in my notes, but from where?

"The final grade should provide a minimum slope of one-half unit vertical in 12 units horizontal for a minimum of 6 feet from the home"

Billy Stephens · #5 (**permalink**) 12-11-2007, 06:56 PM

Quote:

Originally Posted by Michael Thomas

Also, I've got this in my notes, but from where?

"The final grade should provide a minimum slope of one-half unit vertical in 12 units horizontal for a minimum of 6 feet from the home"

IRC 2003 R202 Grade Plane

Gutters? Anyone? 6 ft Requirement.
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.
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Jerry McCarthy · #6 (**permalink**) 12-11-2007, 07:13 PM

This is what proper gutter extensions should look like.

Jerry Peck · #7 (**permalink**) 12-11-2007, 07:14 PM

In Florida the gutter/downspout discharge is required to be at least 12 inches from the foundation wall/slab edge.

Don't know of anything in the IRC.

The purpose is to get the discharging water out past the termite treatment area.

Jerry Peck · #8 (**permalink**) 12-11-2007, 07:15 PM

Jerry Mc.,

Those are just 'outdoor showers'.

http://www.inspectionnews.net/home_i...extension2.jpg

Billy Stephens · #9 (**permalink**) 12-11-2007, 07:50 PM

Quote:

Originally Posted by Jerry McCarthy

This is what proper gutter extensions should look like.

Jerry Mc.,

I hope you wrote up the Improper Clearance from the Ground on that front Siding.

Darren Miller · #10 (**permalink**) 12-12-2007, 05:49 AM

R801.3 (NJ edition)

Roof drainage. In areas where expansive or collapsible soils are known to exist, all dwellings shall have a controlled method of water disposal from roofs that will collect and discharge roof drainage to the ground surface at least 5 feet from foundation walls or to an approved drainage system.

Darren

New Jersey Home Inspection - About the House!

Aaron Miller · #11 (**permalink**) 12-12-2007, 06:01 AM

Michael:

The 6" drop in the first 10' out from the foundation perimeter is also a HUD requirement. Additionally, if the foundation is a slab-on-grade, it is a Post-Tensioning Institute requirement. And finally, if this is a new home covered by a warranty or one where the foundation has been repaired and is under warranty, the warranty validity is dependent upon the owner's adherence with this drainage provision.

Aaron

Rick Hurst · #12 (**permalink**) 12-12-2007, 07:56 AM

Aaron,

Your on the money about the home warranty. I had a PC customer who had filed a claim against the builder / and the home warranty for foundation movement.

As soon as the warranty people came out, they told her she had added those stackable stones around the shrub bed which obstructed the drainage, therefore the warranty was void. According to them, no changes should be made to the original grading whatsoever to keep such a warranty in place.

rick

Richard Rushing · #13 (**permalink**) 12-12-2007, 08:16 AM

Those same warranty folks will deny a claim if you add shrubs or plant trees. Again, these "Warranty" companies are in business to *make* money, not give it away. They will do what ever necessary to drop a claim.

Rich

Billy Stephens · #14 (**permalink**) 12-12-2007, 09:41 AM

Quote:

Originally Posted by Darren Miller

R801.3 (NJ edition)

Roof drainage. In areas where expansive or collapsible soils are known to exist, all dwellings shall have a controlled method of water disposal from roofs that will collect and discharge roof drainage to the ground surface at least 5 feet from foundation walls or to an approved drainage system.

Darren

New Jersey Home Inspection - About the House!

Bingo Thanks Darren,

Also in IRC 2003 R801.3

Gunnar Alquist · #15 (**permalink**) 12-12-2007, 01:59 PM

Jerry Mc,

Nice personal pic. Much more flattering than the last one. Of course, the same could be said about mine...